G. Oksenhendler

Analgésie péridurale après chirurgie thoracique : morphine versus buprénorphine

A double-blind study was carried out to assess the efficiency and possible side-effects of a single epidural injection of either morphine or buprenorphine at equipotent doses after elective thoracic surgery. The series included 24 patients aged 53.7 ± 11.4 years ; 13 underwent a lobectomy and 11 a pneumonectomy. 6 h after the last intravenous injection of fentanyl, the patients were randomly allocated to one of three equal groups. They received an epidural injection at T8–9 or T9–10 level of either 100 μg · kg−1 morphine (group M) or 6.6 μg · kg−1 buprenorphine (group B) or a subcutaneous injection of 0.1 ml · kg−1 normal saline placebo at the same level (group T). The following parameters were measured 20 and 60 min, and every 6 h up to 48 h after the injection : patient wakefulness, respiratory rate, blood gases, pain (according to a verbal scale), FVC and FEV1, adverse effects (euphoria, hallucinations, sweating, facial pruritus, nausea) and atelectasia. The duration of surgery, the anaesthetic protocol, the age, weight and height, as well as all the parameters before injection were similar in all three groups. There was a fall in pain intensity from the 20th min to the 24th hour in group M and from the 20th min to the 36th hour in group B, significant for both groups when compared with group T. Similarly, there was a prolonged increase in FEV1 in both groups M and B. There was no case of severe respiratory depression ; Paco2 was increased at the 1st hour (+ 0.3 ± 0.6 kPa) in group B and at the 6th hour (+ 0.5 ± 0.7 kPa) in group M. Fiberoptic bronchoscopy was required for 6 patients in group T, 2 in group M (p < 0.05) and 1 in group B (p < 0.01). The results showed that a single epidural injection of morphine or buprenorphine was a simple, safe and efficient method of analgesia with minimal side-effects after thoracic surgery. Buprenorphine seemed preferable, because of a longer duration of analgesia.

Exploration des troubles de l'immunité au cours des péritonites postopératoires

Despite major diagnostic and therapeutic advances, postoperative peritonitis appeared to be still associated with a severe prognosis. The failure to react to delayed hypersensitivity skin tests was recently shown to identify patients at increased risk for sepsis. In an attempt to clarify the mechanisms of this anergy, cellular and humoral immunity was studied with in vitro tests in 12 patients treated for postoperative peritonitis. Complement was decreased in 33.3% of cases and normal in the others. No significant change was found in IgG and IgM titres, but IgA concentrations were increased in 80% of cases. A decrease in the total number of lymphocytes was observed in 41.7% of patients, related to the reduction in the total T lymphocyte count. Mitogen-induced lymphocyte transformation was studied with phytohaemagglutinin, concanavalin A, pokeweed-mitogen, and tuberculin purified protein derivative. Six patients had decreased or negative response to at least three mitogens; 91,7% had no response to tuberculin. The leukocyte migration inhibition test was negative in all cases. These abnormalities in cell mediated immunity may have been related to underlying diseases (severe nutrition depletion in 7 cases), to sepsis (septic shock in 10 cases), to repeated anaesthesias and surgical procedures, and even to drugs (e.g. antibiotics). The presence of serum inhibitors may have been the cause of the anergy and further studies are required.